Molecular sieves are classified by the Structure Commission of the International Zeolite Association according to the rules of the IUPAC Commission on Zeolite Nomenclature. According to this classification, framework type zeolites and other crystalline microporous molecular sieves, for which a structure has been established, are assigned a three letter code and are described in the “Atlas of Zeolite Framework Types,” Sixth Revised Edition, Elsevier, 2007.
One known molecular sieve for which a structure has been established is the material designated as MAZ, which is a molecular sieve having a tubular 12-membered ring (12-MR) channel system having a diameter of 7.4 Å. A secondary 8-membered ring (8-MR) channel system having dimensions of 3.4×5.6 Å runs parallel to the 12-MR pore system. Examples of MAZ framework type materials include zeolite omega and ZSM-4. MAZ framework type materials are of interest for application in catalysis, particularly various hydrocarbon conversion reactions such as (hydro)cracking, reforming, isomerization, disproportionation, and alkylation and dealkylation processes.
U.S. Pat. No. 4,241,036 discloses zeolite omega and its synthesis using a tetramethylammonium cation as a structure directing agent.
Great Britain Patent No. 1,117,568 discloses zeolite ZSM-4 and its synthesis in the presence of a tetramethylammonium cation as a structure directing agent.
U.S. Pat. No. 4,021,447 discloses that pyrrolidine and choline salts can be used as structure directing agents in the synthesis of ZSM-4.
U.S. Pat. No. 4,331,643 discloses the synthesis of ZSM-4 using 1,4-diazobicyclo[2.2.2]octane as a structure directing agent.
U.S. Pat. No. 4,377,502 discloses the synthesis of ZSM-4 using various oxygen-containing and oxygen-nitrogen-containing organic compounds as a structure directing agent.
It has now been found that pure phase MAZ framework type zeolites can be prepared using a trimethylphenylammonium cation as a structure directing agent. The resultant MAZ framework type zeolite crystals have an average crystallite size of greater than 5 μm.